Earlier this week, overshadowed by the collapsing of banks and largely unnoticed, something happened that is very important for the future of science. Ten years from now, that unnoticed event may prove to be more important than the banking catastrophe.

The event was that a major scientific publisher, Springer Science+Business Media, acquired BioMed Central, one of the first and most important "open access publishers". Open access publishing of science means not only that everybody everywhere can access the research without any payment but also that the research can be used in creative ways without consent but simply with attribution. Once all of science is open access – as it surely will be eventually – then the value of our scientific deposits may be greatly increased: the totality has a value that exceeds the sum of the parts.

BioMed Central has shown that open access publishing can be profitable, and its acquisition by a major publisher means that open access publishing is becoming mainstream. At the moment, fewer than 10% of scientific articles are published open access, but Springer's acquisition may bring us to the tipping point where open access publishing will be the norm.

Other major publishers may have to follow Springer in promoting open access publishing. Eventually the traditional model – whereby publishers make money by restricting access to scientific research – will surely wither.

I'm no seer, but it became obvious to me in the mid-90s, when as well as being the editor of the British Medical Journal I was the chief executive of the BMJ Publishing Group, that the transition to open access would have to happen. Most research is publicly funded, and when the internet appeared it made no sense for research funders to allow publishers to profit from restricting access to their research – because the value added by publishers is minimal.

Indeed, publishers arguably subtract value by Balkanising the research. Scientific research is fundamentally different from a thing, a car or a banana, in that ideas can be exchanged and increase exponentially without anybody losing. The more people have access to scientific ideas, the more new ideas. Plus the academic community, particularly in the US, was increasingly angry with scientific publishers charging them ever more for research that they had produced. Some journals cost $15,000 for a year's subscription because they contained "must have" information. Academics felt ripped off.

When I told a meeting of scientific publishers at the Frankfurt book fair in the 90s that open access would have to happen, they thought me crazy. Many still do. But every year since then has seen significant steps towards complete open access publishing.

The "author pays" model was invented, whereby authors (actually institutions, usually research funders) paid for peer review and posting on the web up front, meaning that the research, once published, would be open access. BioMed Central was formed and was soon publishing dozens of journals.

The Public Library of Science (where I'm now on the board) started as an advocacy organisation but soon became an open access publisher and has been able in a very short time to publish major open access journals that rival the traditional elite of Nature, Science, Cell, and the like. Following hard on the heels of BioMed Central, PLoS will soon be profitable.

Most significantly major funders of research – led by the Wellcome Trust – have mandated that the research they publish be open access soon after publication. Many universities, including Harvard, have required the same, but the most important step came when the National Institutes of Health, which funds a quarter of the world's biomedical research, mandated that the research it funds be open access within a year of publication.

Progress has been slow because traditional scientific publishers have resisted. This is unsurprising because publishing science has been enormously profitable, with gross margins of over 50%. The publishers came to own immensely valuable information without having to spend anything on generating the value. Robert Maxwell got rich through publishing science, not newspapers.

Another block has been that academic credit has been tied to publishing in the elite journals like Nature and Science, although a paper published in PLoS Medicine this week shows how the scramble to publish in these journals means that the world is presented with a very distorted view of science. The influence of these journals may, however, decline as those who measure the quality of science move from using publication in one of these journals as a marker of excellence to counting citations of individual articles.

It will be fascinating to see how the major journals and traditional publishers react to Springer's acquisition, but Tuesday was undoubtedly a great day for science.